US20190254658A1 - Three Dimensional Adjuncts - Google Patents

Abstract

Stapling assemblies for use with a surgical stapler and methods for manufacturing the same are provided. Three dimensional adjuncts for use with a surgical stapling assembly and methods for manufacturing the same are also provided.

Description

FIELD
• Three dimensional adjuncts and methods for manufacturing the same are provided.
BACKGROUND
• Surgical staplers are used in surgical procedures to close openings in tissue, blood vessels, ducts, shunts, or other objects or body parts involved in the particular procedure. The openings can be naturally occurring, such as passageways in blood vessels or an internal organ like the stomach, or they can be formed by the surgeon during a surgical procedure, such as by puncturing tissue or blood vessels to form a bypass or an anastomosis, or by cutting tissue during a stapling procedure.
• Some surgical staplers require a surgeon to select the appropriate staples having the appropriate staple height for the tissue being stapled. For example, a surgeon could select tall staples for use with thick tissue and short staples for use with thin tissue. In some instances, however, the tissue being stapled does not have a consistent thickness and, thus the staples cannot achieve the desired fired configuration at each staple site. As a result, a desirable seal at or near all of the stapled sites cannot be formed, thereby allowing blood, air, gastrointestinal fluids, and other fluids to seep through the unsealed sites.
• Further, staples, as well as other objects and materials that can be implanted in conjunction with procedures like stapling, generally lack some characteristics of the tissue in which they are implanted. For example, staples and other objects and materials can lack the natural flexibility of the tissue in which they are implanted, and therefore are unable to withstand the varying intra-tissue pressures at the implantation site. This can lead to undesirable tissue tearing, and consequently leakage, at or near the staple site.
• Accordingly, there remains a need for improved instruments and methods that address current issues with surgical staplers.
SUMMARY
• Stapling assemblies for use with a surgical stapler are provided.
• In one exemplary embodiment, a stapling assembly is provided and can include a body having a plurality of staples disposed therein The plurality of staples can be configured to be deployed into tissue. The stapling assembly can also include a three-dimensional compressible adjunct formed from a matrix that includes at least one fused bioabsorbable polymer. The adjunct can be configured to be releasably retained on the body such that the adjunct can be attached to the tissue by the plurality of staples in the body. The adjunct can have a variable stiffness profile such that when the adjunct is in a tissue deployed state, the adjunct can be configured to apply a stress at or above a minimum stress threshold to the tissue for at least about 3 days. In one embodiment, the minimum stress threshold can be at least about 3 g/mm².
• In one aspect, the plurality of staples can have a height of about 0.130 inches or less when in a formed configuration.
• In certain aspects, the at least one fused bioabsorbable polymer can be selected from the group consisting of thermoplastic absorbable polyurethane, ultraviolet curable absorbable polyurethane, poly(lactic acid), polycaprolactone, polyglycolide, polydioxanone, poly(lactic-co-glycolic acid), polyglycolic acid, trimethylene carbonate, glycolide, dioxanone, polyester, copolymers thereof, and combinations thereof.
• The adjunct can have a variety of configurations. For example, the adjunct can have a stiffness that increases as the adjunct compresses. In one embodiment, the adjunct can have compressible internal struts that can be substantially spiral-shaped and can have a predetermined compressed height to limit an amount of compression of the adjunct. In another embodiment, the adjunct can have a plurality of interconnected struts each having two bend zones. The first bend zone can be configured to bend when the adjunct is compressed under a first stress and the second bend zone can be configured to bend when the adjunct is compressed under a second stress that is greater than the first stress.
• In some aspects, the adjunct can have a plurality of internal substantially vertical columns. In one embodiment, the plurality of columns can include a first set of columns having a first length and a second set of columns having a second length that is less than the first length.
• In one aspect, the adjunct can include at least one stop element that can be configured to limit an amount of compression of the adjunct.
• In another exemplary embodiment, a stapling assembly can be provided that includes a body having a plurality of staples disposed therein. The plurality of staples can be configured to be deployed into tissue. The stapling assembly can also include a three-dimensional compressible adjunct formed from a matrix that includes at least one fused bioabsorbable polymer. The adjunct can be configured to be releasably retained on the body such that the adjunct can be attached to tissue by the plurality of staples in the body. The adjunct can have a first stiffness when compressed a first amount and a second stiffness when compressed a second amount greater than the first amount.
• In one aspect, the adjunct can be configured to apply a stress of at least about 3 g/mm²to the tissue stapled thereto for at least 3 days when the adjunct is in a tissue deployed state.
• In certain aspects, the at least one fused bioabsorbable polymer can be selected from the group consisting of thermoplastic absorbable polyurethane, ultraviolet curable absorbable polyurethane, poly(lactic acid), polycaprolactone, polyglycolide, polydioxanone, poly(lactic-co-glycolic acid), polyglycolic acid, trimethylene carbonate, glycolide, dioxanone, polyester, copolymers thereof, and combinations thereof.
• The adjunct can have a variety of configurations. For example, the adjunct can have compressible internal struts that can be substantially spiral-shaped and can have a predetermined compressed height to limit an amount of compression of the adjunct. In one embodiment, the adjunct can have a plurality of interconnected struts each having two bend zones. The first bend zone can be configured to bend when the adjunct is compressed the first amount and the second bend zone can be configured to bend when the adjunct is compressed the second amount.
• In some aspects, the adjunct can have a plurality of internal substantially vertical columns. The plurality of columns can include a first set of columns having a first length and a second set of columns having a second length that is less than the first length.
• In another aspect, the adjunct can include at least one stop element that can be configured to limit an amount of compression of the adjunct.
BRIEF DESCRIPTION OF THE DRAWINGS
• This invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
• FIG. 1 is a perspective view of one exemplary embodiment of a conventional surgical stapling and severing instrument;
• FIG. 2 is a perspective view of a wedge sled of a staple cartridge of the surgical stapling and severing instrument ofFIG. 1;
• FIG. 3 is a perspective view of a knife and firing bar (“E-beam”) of the surgical stapling and severing instrument ofFIG. 1;
• FIG. 4 is a longitudinal cross-sectional view of a surgical cartridge that can be disposed within the stapling and severing instrument ofFIG. 1;
• FIG. 5 is a top view of a staple in an unfired (pre-deployed) configuration that can be disposed within the staple cartridge of the surgical cartridge assembly ofFIG. 4;
• FIG. 6 is a longitudinal cross-sectional view of an exemplary embodiment of a surgical cartridge assembly having an adjunct attached to a cartridge deck;
• FIG. 7 is a schematic illustrating the adjunct ofFIG. 6 in a tissue deployed condition;
• FIG. 8A is a perspective view of one exemplary embodiment of an adjunct having a plurality of repeating units of interconnected struts;
• FIG. 8B is a magnified view of a repeating unit of the adjunct shown inFIG. 8A taken at8B;
• FIG. 9A is a schematic illustration of the repeating unit ofFIG. 8B in a precompressed state;
• FIG. 9B is a schematic illustration of the repeating unit ofFIG. 8B in a first compressed state;
• FIG. 9C is a schematic illustration of the repeating unit shown ofFIG. 8B in a second compressed state;
• FIG. 10 is a graphical illustration of the relationship between stiffness and compression of an adjunct;
• FIG. 11A is a perspective view of an exemplary embodiment of an adjunct having a plurality of interconnected struts and inner connectivity features;
• FIG. 11B is a perspective cross-sectional view of the adjunct shown inFIG. 11A taken at11B;
• FIG. 12A is a perspective view of another exemplary embodiment of an adjunct having a plurality of interconnected struts and linking members;
• FIG. 12B is a magnified view of a repeating unit of the adjunct shown inFIG. 12A taken at12B;
• FIG. 13A is a perspective view of another exemplary embodiment of an adjunct having a plurality of struts of a first material that are interconnected at joints or nodes of a second material;
• FIG. 13B is a magnified view of a repeating unit of the adjunct shown inFIG. 13A taken at13B;
• FIG. 14 is a perspective view of yet another exemplary embodiment of a repeating unit of interconnected struts with end shapes;
• FIG. 15 is a perspective view of an adjunct according to another embodiment having a plurality of struts and at least one stopping element;
• FIG. 16 is a perspective view of an exemplary embodiment of an adjunct having a plurality of struts that are substantially spiral-shaped;
• FIG. 17 is a perspective view of another exemplary embodiment of an adjunct that includes a plurality of struts in the form of vertical columns having different lengths;
• FIG. 18A is a schematic illustration of the adjunct shown inFIG. 17 at a precompressed height;
• FIG. 18B is a schematic illustration of the adjunct shown inFIG. 17 at a first compressed height;
• FIG. 18C is a schematic illustration of the adjunct shown inFIG. 17 at a second compressed height;
• FIG. 19 is a side view of an exemplary embodiment of an adjunct that includes a plurality of struts in the form of vertical columns and curved columns;
• FIG. 20 is a graphical representation of the mechanical behavior of the adjunct shown inFIG. 19 over a compression range;
• FIG. 21A is a perspective view of another exemplary embodiment of an adjunct having a channel configured to receive a cutting element and having tabs for attaching the adjunct to a staple cartridge;
• FIG. 21B is an exemplary embodiment of a staple cartridge assembly having the adjunct shown inFIG. 21A attached to a cartridge body; and
• FIG. 22 is an exemplary embodiment of an adjunct having bridging members.
DETAILED DESCRIPTION
• Certain exemplary embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the instruments and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those skilled in the art will understand that the instruments, systems, and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the present invention is defined solely by the claims. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Such modifications and variations are intended to be included within the scope of the present invention.
• Further, in the present disclosure, like-named components of the embodiments generally have similar features, and thus within a particular embodiment each feature of each like-named component is not necessarily fully elaborated upon. Additionally, to the extent that linear or circular dimensions are used in the description of the disclosed systems, instruments, and methods, such dimensions are not intended to limit the types of shapes that can be used in conjunction with such systems, instruments, and methods. A person skilled in the art will recognize that an equivalent to such linear and circular dimensions can easily be determined for any geometric shape. Sizes and shapes of the systems and instruments, and the components thereof, can depend at least on the anatomy of the subject in which the systems and instruments will be used, the size and shape of components with which the systems and instruments will be used, and the methods and procedures in which the systems and instruments will be used.
• It will be appreciated that the terms “proximal” and “distal” are used herein with reference to a user, such as a clinician, gripping a handle of an instrument. Other spatial terms such as “front” and “rear” similarly correspond respectively to distal and proximal. It will be further appreciated that for convenience and clarity, spatial terms such as “vertical” and “horizontal” are used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these spatial terms are not intended to be limiting and absolute.
• Values or ranges may be expressed herein as “about” and/or from/of “about” one particular value to another particular value. When such values or ranges are expressed, other embodiments disclosed include the specific value recited and/or from/of the one particular value to another particular value. Similarly, when values are expressed as approximations, by the use of antecedent “about,” it will be understood that here are a number of values disclosed therein, and that the particular value forms another embodiment. It will be further understood that there are a number of values disclosed therein, and that each value is also herein disclosed as “about” that particular value in addition to the value itself. In embodiments, “about” can be used to mean, for example, within 10% of the recited value, within 5% of the recited value or within 2% of the recited value.
• For purposes of describing and defining the present teachings, it is noted that unless indicated otherwise, the term “substantially” is utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. The term “substantially” is also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.
• Surgical stapling assemblies and methods for manufacturing the same and for stapling tissue are provided. In general, a stapling assembly is provided having a body (e.g., a staple cartridge or end effector body) with a plurality of staples disposed therein. The stapling assembly also includes a three-dimensional compressible adjunct formed from a matrix that includes at least one fused bioabsorbable polymer and configured to be releasably retained on the body. The adjunct can be releasably retained to the body such that when a staple is deployed from the body and into tissue, at least a portion of the adjunct can attach to the tissue captured by the staple. As discussed herein, the adjunct can be configured to compensate for variations in tissue properties, such as variations in the tissue thickness, and/or promote tissue ingrowth when the adjunct is stapled to tissue. For example, the adjunct can be configured to apply a stress of at least about 3 g/mm²to tissue for at least 3 days when in a tissue deployed state (e.g., when the adjunct is stapled to tissue in vivo).
• An exemplary stapling assembly can include a variety of features to facilitate application of a surgical staple, as described herein and illustrated in the drawings. However, a person skilled in the art will appreciate that the stapling assembly can include only some of these features and/or it can include a variety of other features known in the art. The stapling assemblies described herein are merely intended to represent certain exemplary embodiments. Moreover, while the adjuncts are described in connection with surgical staple cartridge assemblies, and need not be replaceable, the adjuncts can be used in connection with staple reloads that are not cartridge based or any type of surgical instrument.
• FIG. 1 illustrates an exemplary surgical stapling and severinginstrument100 suitable for use with an implantable adjunct. The illustrated surgical stapling and severinginstrument100 includes astaple applying assembly106 or end effector having ananvil102 pivotably coupled to an elongatestaple channel104. Thestaple applying assembly106 can be attached at its proximal end to anelongate shaft108 forming an implementportion110. When thestaple applying assembly106 is closed, or at least substantially closed, the implementportion110 can present a sufficiently small cross-section suitable for inserting thestaple applying assembly106 through a trocar. While theinstrument100 is configured to staple and sever tissue, surgical instruments configured to staple but not sever tissue are also contemplated herein.
• In various instances, thestaple applying assembly106 can be manipulated by ahandle112 connected to theelongate shaft108. Thehandle112 can include user controls such as arotation knob114 that rotates theelongate shaft108 and thestaple applying assembly106 about a longitudinal axis of theelongate shaft108, and aclosure trigger116 which can pivot in front of apistol grip118 to close thestaple applying assembly106. Aclosure release button120 can be outwardly presented on thehandle112 when theclosure trigger116 is clamped such that theclosure release button120 can be depressed to unclamp theclosure trigger116 and open thestaple applying assembly106, for example.
• A firingtrigger122, which can pivot in front of theclosure trigger116, can cause thestaple applying assembly106 to simultaneously sever and staple tissue clamped therein. In various instances, multiple firing strokes can be employed using thefiring trigger122 to reduce the amount of force required to be applied by the surgeon's hand per stroke. In certain embodiments, thehandle112 can include one or more rotatable indicator wheels such as, for example,rotatable indicator wheel124 which can indicate the firing progress. A manualfiring release lever126 can allow the firing system to be retracted before full firing travel has been completed, if desired, and, in addition, the firingrelease lever126 can allow a surgeon, or other clinician, to retract the firing system in the event that the firing system binds and/or fails.
• Additional details on the surgical stapling and severinginstrument100 and other surgical stapling and severing instruments suitable for use with the present disclosure are described, for example, in U.S. Pat. No. 9,332,984 and in U.S. Patent Application Publication No. 2009/0090763, the disclosure of which is incorporated herein by reference in their entirety. Further, the surgical stapling and severing instrument need not include a handle, but instead a housing that is configured to couple to a surgical robot, for example, as described in U.S. application Ser. No. 15/689,198, filed on Aug. 29, 2017 to Frederick E. Shelton et al., the disclosure of which is incorporated herein by reference in its entirety.
• With reference toFIGS. 2 and 3, a firing assembly such as, for example, firingassembly228, can be utilized with a surgical stapling and severing instrument, such asinstrument100 inFIG. 1. The firingassembly228 can be configured to advance awedge sled230 having a plurality ofwedges232 configured to deploy staples from a staple applying assembly, likestaple applying assembly106 inFIG. 1, into tissue captured between an anvil, likeanvil102 inFIG. 1, and an elongate staple channel, likechannel104 inFIG. 1. Furthermore, anE-beam233 at a distal portion of the firingassembly228 may fire the staples from the staple applying assembly as well as position the anvil relative to the elongate staple channel during firing. The illustratedE-beam233 includes a pair oftop pins234, a pair ofmiddle pins236 which may followportion238 of thewedge sled230, and a bottom pin orfoot240. The E-beam233 can also include asharp cutting edge242 configured to sever the captured tissue as the firingassembly228 is advanced distally. In addition, integrally formed and proximally projectingtop guide244 andmiddle guide246 bracketing each vertical end of thecutting edge242 may further define atissue staging area248 assisting in guiding tissue to thesharp cutting edge242 prior to being severed. Themiddle guide246 may also serve to engage and fire the staple applying assembly by abutting a steppedcentral member250 of thewedge sled230 that effects staple formation by the staple applying assembly.
• Referring toFIG. 4, astaple cartridge400 can be utilized with a surgical stapling and severing instrument, like surgical stapling and severinginstrument100 inFIG. 1, and can include acartridge body402 and a plurality ofstaple cavities404 within thecartridge body402. A staple406 can be removably positioned in eachstaple cavity404. The staple406 in a unfired (pre-deployed, unformed) configuration is shown in more detail inFIG. 5. Thestaple cartridge400 can also include a longitudinal channel that can be configured to receive a firing and/or cutting member, e.g., an E-beam, likeE-beam233 inFIG. 3.
• Each staple406 can include a crown (base)406_Cand one ormore legs406_Lextending from thecrown406_C. Prior to thestaples406 being deployed, thecrowns406_Cof thestaples406 can be supported bystaple drivers408 positioned within thestaple cartridge400 and, concurrently, thelegs406_Lof thestaples406 can be at least partially contained within thestaple cavities404. Further, thestaple legs406_Lof thestaples406 can extend beyond the tissue-contactingsurface410 of thestaple cartridge400 when thestaples406 are in their unfired positions. In certain instances, as shown inFIG. 5, the tips of thestaple legs406_Lcan be sharp which can incise and penetrate tissue.
• In some implementations, the staples can include one or more external coatings, e.g., a sodium sterate lubricant and/or an antimicrobial agent(s). The antimicrobial agent(s) can be applied to the staples as its own coating or incorporated into another coating, such as a lubricant. Non-limiting examples of suitable antimicrobial agents include 5-Chloro-2-(2,4-dichlorophenoxy)phenol, chlorhexidine, silver formulations (like nano-crystalline silver), lauric arginate ethyl ester (LAE), octenidine, polyhexamethylene biguanide (PHMB), taurolidine, lactic acid, citric acid, acetic acid, and their salts.
• Thestaples406 can be deformed from an unfired position into a fired position such that thelegs406_Lmove through thestaple cavities404, penetrate tissue positioned between an anvil, likeanvil102 inFIG. 1, and thestaple cartridge400, and contact the anvil. As thelegs406_Lare deformed against the anvil, thelegs406_Lof each staple406 can capture a portion of the tissue within each staple406 and apply a compressive force to the tissue. Further, thelegs406_Lof each staple406 can be deformed downwardly toward thecrown406_Cof the staple406 to form a staple entrapment area in which the tissue can be captured therein. In various instances, the staple entrapment area can be defined between the inner surfaces of the deformed legs and the inner surface of the crown of the staple. The size of the entrapment area for a staple can depend on several factors such as the length of the legs, the diameter of the legs, the width of the crown, and/or the extent in which the legs are deformed, for example.
• In use, an anvil, likeanvil102 inFIG. 1, can be moved into a closed position by depressing a closure trigger, likeclosure trigger116 inFIG. 1, to advance an E-beam, likeE-beam233 inFIG. 3. The anvil can position tissue against a tissue-contactingsurface410 of thestaple cartridge400. Once the anvil has been suitably positioned, thestaples406 can be deployed.
• To deploystaples406, as discussed above, a staple-firing sled, likesled230 inFIG. 2, can be moved from aproximal end400p toward adistal end400d of thestaple cartridge400. As a firing assembly, like firingassembly228 inFIG. 3, is advanced, the sled can contact thestaple drivers408 and lift thestaple drivers408 upwardly within thestaple cavities404. In at least one example, the sled and thestaple drivers408 can each include one or more ramps, or inclined surfaces, which can co-operate to move thestaple drivers408 upwardly from their unfired positions. As thestaple drivers408 are lifted upwardly within theirrespective staple cavities404, thestaples406 are advanced upwardly such that thestaples406 emerge from theirstaple cavities404 and penetrate into tissue. In various instances, the sled can move several staples upwardly at the same time as part of a firing sequence.
• A person skilled in the art will appreciate that, while adjuncts are shown and described below, the adjuncts disclosed herein can be used with other surgical instruments, and need not be coupled to a staple cartridge as described. Further, a person skilled in the art will also appreciate that the staple cartridges need not be replaceable.
• As discussed above, with some surgical staplers, a surgeon is often required to select the appropriate staples having the appropriate staple height for the tissue that is to be stapled. For example, a surgeon could select tall staples for use with thick tissue and short staples for use with thin tissue. In some instances, however, the tissue being stapled does not have a consistent thickness and thus, the staples cannot achieve the desired fired configuration for every section of the stapled tissue (e.g., thick and thin tissue sections). The inconsistent thickness of tissue can also lead to undesirable leakage and/or tearing of tissue at the staple site when staples with the same or substantially height are used, particularly when the staple site is exposed to intra-pressures at the staple site and/or along the staple line.
• Accordingly, various embodiments of three-dimensionally printed adjuncts are provided that can be configured to compensate for varying thickness of tissue that is captured within fired (deployed) staples to avoid the need to take into account staple height when stapling tissue during surgery. That is, the adjuncts described herein can allow a set of staples with the same or similar heights to be used in stapling tissue of varying thickness (i.e., from thin to thick tissue) while also, in combination with the adjunct, providing adequate tissue compression within and between fired staples. Thus, the adjuncts described herein can maintain suitable compression against thin or thick tissue stapled thereto to thereby minimize leakage and/or tearing of tissue at the staple sites.
• Alternatively or in addition, the three-dimensionally printed adjuncts can be configured to promote tissue ingrowth. In various instances, it is desirable to promote the ingrowth of tissue into an implantable adjunct, to promote the healing of the treated tissue (e.g. stapled and/or incised tissue), and/or to accelerate the patient's recovery. More specifically, the ingrowth of tissue into an implantable adjunct may reduce the incidence, extent, and/or duration of inflammation at the surgical site. Tissue ingrowth into and/or around the implantable adjunct may manage the spread of infections at the surgical site, for example. The ingrowth of blood vessels, especially white blood cells, for example, into and/or around the implantable adjunct may fight infections in and/or around the implantable adjunct and the adjacent tissue. Tissue ingrowth may also encourage the acceptance of foreign matter (e.g., the implantable adjunct and the staples) by the patient's body and may reduce the likelihood of the patient's body rejecting the foreign matter. Rejection of foreign matter may cause infection and/or inflammation at the surgical site.
• Unlike conventional adjuncts (e.g., adjuncts that are not three-dimensionally printed, such as woven adjuncts), these three-dimensionally printed adjuncts can be formed with microstructures (units) that are consistent and reproducible. That is, unlike with other methods of manufacture, 3D printing significantly improves control over microstructural features such as e.g., placement and connection of elements. As a result, variability in both the microstructure(s) and attendant properties of the adjunct is decreased, as compared to conventional woven adjuncts. For example, these three-dimensionally printed adjuncts can be structured such that they compress a predetermined amount in a substantially uniform matter. The fine control over the microstructure can also allow the porosity of the adjunct to be tailored to enhance tissue ingrowth. Further, these three-dimensionally printed adjuncts can be adapted for use with a variety of staples and tissue types.
• In general, the adjuncts provided herein are designed and positioned atop a body, likecartridge body402 inFIG. 4. When the staples are fired (deployed) from the body, the staples penetrate through the adjunct and into tissue. As the legs of the staple are deformed against the anvil that is positioned opposite the staple cartridge assembly, the deformed legs capture a portion of the adjunct and a portion of the tissue within each staple. That is, when the staples are fired into tissue, at least a portion of the adjunct becomes positioned between the tissue and the fired staple. While the adjuncts described herein can be configured to be attached to a cartridge body of a staple cartridge assembly, it is also contemplated herein that the adjuncts can be configured to mate with other instrument components, such as a jaw of a surgical stapler. A person of ordinary skill will appreciate that the adjuncts provided herein can be used with replaceable cartridges or staple reloads that are not cartridge based.
• FIG. 6 illustrates an exemplary embodiment of astaple cartridge assembly600 that includes astaple cartridge602 and an adjunct604. Aside from the differences described in detail below, thestaple cartridge602 can be similar to staple cartridge400 (FIG. 4) and is therefore not described in detail herein. As shown, the adjunct604 is positioned against thestaple cartridge602. The staple cartridge can include acartridge body606 and a plurality ofstaples608 disposed therein, likestaples406 shown inFIGS. 4 and 5. Thestaples608 can be any suitable unformed (pre-deployed) height. For example, thestaples608 can have an unformed height between about 2 mm to 4.8 mm. Prior to deployment, the crowns of thestaples608 can be supported bystaple drivers610.
• In the illustrated embodiment, the adjunct604 can be mated to anouter surface612, for example a tissue-contacting surface, of thecartridge body606. In some embodiments, theouter surface612 of thecartridge body606 can include one or more attachment features. The one or more attachments features can be configured to engage the adjunct604 to avoid undesirable movements of the adjunct604 relative to thecartridge body606 and/or premature release of the adjunct604 from thecartridge body606. Exemplary attachment features can be found in U.S. Patent Publication No. 2016/0106427, which is incorporated by reference herein in its entirety.
• The adjunct604 is compressible to permit the adjunct to compress to varying heights to thereby compensate for different tissue thickness that are captured within a deployed staple. The adjunct604 has an uncompressed (undeformed), or pre-deployed, height and is configured to deform to one of a plurality of compressed (deformed), or deployed, heights. For example, the adjunct604 can have an uncompressed height which is greater than the fired height of the staples608 (e.g., the height (H) of the firedstaple608ainFIG. 7). That is, the adjunct604 can have an undeformed state in which a maximum height of the adjunct604 is greater than a maximum height of a firedstaple608a(i.e., a staple that is in a formed configuration). In one embodiment, the uncompressed height of the adjunct604 can be about 10% taller, about 20% taller, about 30% taller, about 40% taller, about 50% taller, about 60% taller, about 70% taller, about 80% taller, about 90% taller, or about 100% taller than the fired height of thestaples608. In certain embodiments, the uncompressed height of the adjunct604 can be over 100% taller than the fired height of thestaples608, for example.
• The adjunct604 can be releasably mated to theouter surface612 of thecartridge body606. As shown inFIG. 7, when the staples are fired, tissue (T) and a portion of the adjunct604 are captured by the fired (formed)staples608a.The firedstaples608aeach define the entrapment area therein, as discussed above, for accommodating the capturedadjunct604 and tissue (T). The entrapment area defined by a firedstaple608ais limited, at least in part, by a height (H) of the firedstaple608a.For example, the height of a firedstaple608acan be about 0.160 inches or less. In some embodiments, the height of a first stapled608acan be about 0.130 inches or less. In one embodiment, the height of a firedstaple608acan be from about 0.020 inches to 0.130 inches. In another embodiment, the height of a firedstaple608acan be from about 0.060 inches to 0.160 inches.
• As described above, the adjunct604 can be compressed within a plurality of fired staples whether the thickness of the tissue captured within the staples is the same or different within each fired staple. In at least one exemplary embodiment, the staples within a staple line, or row, can be deformed such that the fired height is about 2.75 mm, for example, where the tissue (T) and the adjunct604 can be compressed within this height. In certain instances, the tissue (T) can have a compressed height of about 1.0 mm and the adjunct604 can have a compressed height of about 1.75 mm. In certain instances, the tissue (T) can have a compressed height of about 1.50 mm and the adjunct604 can have a compressed height of about 1.25 mm. In certain instances, the tissue (T) can have a compressed height of about 1.75 mm and the adjunct604 can have a compressed height of about 1.00 mm. In certain instances, the tissue (T) can have a compressed height of about 2.00 mm and the adjunct604 can have a compressed height of about 0.75 mm. In certain instances, the tissue (T) can have a compressed height of about 2.25 mm and the adjunct604 can have a compressed height of about 0.50 mm. Accordingly, the sum of the compressed heights of the captured tissue (T) andadjunct604 can be equal, or at least substantially equal, to the height (H) of the firedstaple608a.
• As discussed in more detail below, the structure of the adjunct can be configured such that when the adjunct and tissue are captured within the fired staple, the adjunct can apply a stress that can withstand the pressure of circulating blood through tissue. High blood pressure is typically considered 210 mmHg, and therefore it would be desirable for the adjunct to apply a stress to the tissue that is equal to or greater than 210 mmHg (e.g., 3 g/mm²) for a predetermined time period (e.g., 3 days). As such, in certain embodiments, the adjunct can be configured to apply a stress of at least about 3 g/mm²to the captured tissue for at least 3 days. The adjunct is in a tissue deployed state when the adjunct is stapled to tissue in vivo. In one embodiment, the applied stress can be about 3 g/mm². In another embodiment, the applied stress can be greater than 3 g/mm². In yet another embodiment, the stress can be at least about 3 g/mm²and applied to the captured tissue for more than 3 days. For example, in one embodiment, the stress can be at least about 3 g/mm²and applied to captured tissue for about 3 days to 5 days.
• In order to design an adjunct that is configured to apply a stress of at least about 3 g/mm²to the captured tissue for a predetermined time, one can use the principles of Hooke's law (F=kD). For example, when the force (stress) to be applied to the captured tissue is known, one can design an adjunct to have a stiffness (k). The stiffness can be set by tuning the geometry of the adjunct (e.g., the diameter of the struts and/or the interconnectivity of the struts, e.g., angles and space between the struts). Further, one can design the adjunct to have a maximum amount of compression displacement for a minimum thickness of tissue, e.g., 1 mm, and therefore the length of displacement D can be the combination of a minimum thickness of tissue, e.g., 1 mm, plus a thickness of the adjunct when stapled to tissue for a given max staple height, e.g., 2.75 mm. By way of example, in one embodiment, an adjunct can be structured to have a height that is greater than a maximum formed stapled height of 2.75 mm and to compress to a height of 1.75 mm when stapled to tissue having a minimum thickness of 1 mm. Therefore, the adjunct can vary in compressibility to maintain a constant length of displacement D such that the stiffness (k) and total thickness (D) of captured tissue and adjunct can apply a stress of 3 g/mm²to the captured tissue. It should be noted a person of ordinary skill in the art will appreciate that the foregoing formula can be modified to take into account variations in temperatures, e.g., when the adjunct is brought from room temperature to body temperature after implantation.
• Additionally, the adjunct can be further developed to provide a substantially continuous stress to the captured tissue (e.g., 3 g/mm²) for a predetermined time (e.g., 3 days). To achieve this, one would need to take into account the degradation rate of the materials of the adjunct and the rate of tissue ingrowth within the adjunct when designing the adjunct. In doing so, one can design an adjunct such that the stiffness of the adjunct and/or the total thickness of the captured tissue and adjunct do not vary in a way that could effect an applied stress that is less than 3 g/mm².
• An adjunct is stapled to tissue under various stapling conditions (e.g., tissue thickness, height of formed staple, intra-tissue pressure). Depending on the stapling condition, one can determine an effective amount of stress that the adjunct needs to be able to apply to the tissue to prevent tissue tearing and leakage. For example, in one embodiment, an effective amount of stress is at least about 3 g/mm². In order for the adjunct to provide an effective amount of stress to the tissue, the adjunct can be designed to effectively compensate for the various stapling conditions. As such, the geometry of the adjunct can be tailored to assume different compressed heights when stapled to tissue. As there is a finite range of intra-tissue pressures, tissue thicknesses, and formed staple heights, one can determine appropriate geometric structures for the adjunct that can be effective in applying a substantially continuous desired stress to the tissue (e.g., 3 g/mm²) when stapled thereto for a given amount of time (e.g., at least 3 days) over a range of stapling conditions. That is, as described in more detail below, the present adjuncts are formed of compressible materials and geometrically configured so as to allow the adjunct to compress to various heights in predetermined planes when stapled to tissue. Further, this varied response by the adjunct can also allow the adjunct to maintain its application of a continuous desired stress to the tissue when exposed to fluctuations in intra-tissue pressure that can occur when the adjunct is stapled to tissue (e.g., a spike in blood pressure).
• The adjuncts can be manufactured by additive manufacturing, also known as three-dimensional printing or 3D printing. 3D printing is a high-speed additive manufacturing technology that can deposit various types of materials in a printer-like fashion. That is, 3D printing is achieved by laying down successive layers of material to form shapes. To print, the printer reads the model design from a digital file and lays down successive layers of material to build a series of cross sections. These layers, as decided by the model, are joined or automatically fuse to create the final shape. This technique allows for the ability to create various shapes or geometric features with control and precision. Non-limiting examples of suitable 3D printing processes, also known as additive manufacturing, as classified by ASTM committee 42 include VAT photopolymerication (e.g., stereolithography) in which liquid photopolymer in a vat is selectively cured by light activated polymerization; material jetting in which droplets of build material are selectively deposited; binder jetting in which a liquid bonding agent is selectively deposited to join powder materials; powder bed diffusion (e.g., selective laser sintering) in which thermal energy selectively fuses regions of a powder bed; direct energy deposition in which focused thermal energy is used to fuse materials by melting as they are being deposited; direct energy deposition in which focused thermal energy is used to fuse materials by melting as they are being deposited; material extrusion (e.g., fused deposition modeling) in which material is selectively dispensed through a nozzle or orifice; and sheet lamination in which sheets of material are bonded to form an object.
• For example, in some embodiments, the method can include scanning a beam to melt a plurality of layers of powder to form a compressible, bioabsorbable adjunct having an elongate body with a tissue-contacting surface, a cartridge-contacting surface that is opposite the tissue-contacting surface, and a plurality of struts forming repeating geometric units that extend between the tissue-contacting and cartridge-contacting surfaces. In one embodiment, the method can also include coating the adjunct with one or more anti-microbial agents.
• The adjunct can be formed from one or more matrices. In certain embodiments, the one or more matrices can be in the form of a particulate matrix. In such instances, each particulate matrix can be formed of fused particles (e.g., fused bioabsorbable polymer particles).
• In general, each matrix can be formed of at least one fused polymer. The at least one fused polymer can be selected so as to impart a desired compressibility to the adjunct. For example, in one embodiment, the matrix includes a fused polymer, whereas in other embodiments, the matrix can include two or more fused polymers that are different. Alternatively, or additionally, where the adjunct includes two or more matrices, each matrix can be formed of the same fused polymer or different fused polymers relative to each other. For example, a first matrix can include a first fused polymer and a second matrix can include a second fused polymer that is either more or less flexible than the first fused polymer. In this way, the fused polymers can provide the adjunct with varying flexibility. Further, the fused polymers can have differing degradation rates, such that the compressibility of the adjunct can be tailored to vary over time as function of the degradation rates.
• While various types of materials can be used, in some embodiments, the at least one fused polymer is a bioabsorbable polymer. Non-limiting examples of suitable bioabsorbable polymers include thermoplastic absorbable polyurethane, ultraviolet curable bioabsorbable polyurethane, poly(lactic acid) (PLA), polycaprolactone (PCL), polyglycolide, polydioxanone (PDS), poly(lactic-co-glycolic acid) (PLGA), polyglycolic acid, trimethylene carbonate, glycolide, dioxanone, polyester, any copolymers thereof, or any combinations thereof. Additional non-limiting examples of suitable bioabsorbable polymers include macromers with acrylate or methacrylate end group modified three-armed hydroxyl terminated PCL or Poly (DL-lactide), PLA-PEG or poly(trimethylenecarbonate), PEG dimethyl or trimethyl acrylate or methacrylate, polypropylene fumarate, L-lactide/caprolactone copolymers, PLGA polymers infiltrated with collagen, PCL-tricalcium phosphate (TCP), PLGA-TCP copolymers coated with Hyaluronic acid, PCL-PLGA-TCP, PLGA-PCL copolymers, PDS polymers and copolymers, PCL polymer and Hyaluronic acid, PCL and Beta-Tricalcium phosphate with collagen coating, polyvinyl alcohol, calcium phosphate/poly(hydroxybutyrate-co-valerate), and calcium hydroxyapatite/poly-L-lactide.
• For example, in some embodiments, the adjunct can be formed of various components each being formed of a matrix that includes at least one fused bioabsorbable polymer. In some embodiments, the adjunct can have a first component formed from a first matrix of at least one fused bioabsorbable polymer (e.g., polyglactin or polydioxanone) and a second component formed from a second matrix that includes at least one fused bioabsorbable polymer (e.g., a polycaprolactone copolymer). The at least one fused bioabsorbable polymer for each matrix can include at least two different bioabsorbable polymers. In one embodiment, the first component can have a first color and the second component can have a second color that differs from the first color.
• In some embodiments, the adjunct can be drug eluting. For example, one or more components of the adjunct can include a composition having a pharmaceutically active agent. The composition may release a therapeutically effective amount of the pharmaceutically active agent. In various embodiments, the pharmaceutically active agent can be released as the adjunct is desorbed/absorbed. In various embodiments, the pharmaceutically active agent may be released into fluid, such as, for example, blood, passing over or through the adjunct. Non-limiting examples of pharmaceutically active agents include haemostatic agents and drugs, such as, for example, fibrin, thrombin, and oxidized regenerated cellulose (ORC); anti-inflammatory drugs, such as, for example, diclofenac, aspirin, naproxen, sulindac, and hydrocortisone; antibiotic and antimicrobial drug or agents, such as, for example, triclosan, ionic silver, ampicillin, gentamicin, polymyxin B, and chloramphenicol; and anticancer agents, such as, for example, cisplatin, mitomycin, and adriamycin.
• The adjunct can also include an external coating. The coating may be part of the 3D printing process or secondarily applied to the adjunct. For example, in some implementations, the adjunct can be partially or completely coated with antimicrobial agents. Non-limiting examples of suitable anti-microbial agents include triclosan, chlorhexidine, silver formulations (like nano-crystalline silver), lauric arginate ethyl ester (LAE), octenidine, polyhexamethylene biguanide (PHMB), taurolidine; lactic acid, citric acid, acetic acid, and their salts.
• The adjunct, or any component thereof, can be at least partially coated with a bioabsorbable polymer that is different than the at least one fused bioabsorbable polymer of the adjunct. In this way, one or more properties of the adjunct can be varied from the properties of its base material(s) (e.g., fused bioabsorbable polymer(s)). For example, the adjunct can be coated with bioabsorbable polymer(s) that improve(s) structural stability. Alternatively, or in addition to, the adjunct can be coated with a bioabsorbable polymer having a slower degradation rate compared to the degradation rate of the at least one fused bioabsorbable polymer of the adjunct. In this way, the longevity of the adjunct can be increased without sacrificing the desired compressibility of the adjunct provided at least in part by the at least one fused bioabsorbable polymer.
• The adjuncts can have a variety of configurations. In general, the adjuncts can include a tissue-contacting surface, an opposite body-contacting surface (e.g., a cartridge-contacting layer), and an elongate body positioned therebetween (structural layer). The tissue-contacting and cartridge-contacting surfaces can, in certain embodiments, have a structure that differs from the structural layer, so as to form tissue-contacting and cartridge-contacting layers. In some embodiments, the elongate body is formed of multiple struts. The struts can have various configurations, and in certain exemplary embodiments the struts can form interconnected repeating geometric units.
• In some embodiments, the tissue-contacting layer can include a plurality of surface features thereon that are configured to engage tissue located between the adjunct and the anvil so as to substantially prevent sliding movement of the tissue relative to the adjunct during stapling. These surface features can also be configured to minimize sliding movement of the adjunct relative to the tissue when the adjunct is stapled thereto. These surface features can have a variety of configurations. For example, the surface features can extend from the tissue-contacting surface at a distance from about 0.007 inches to 0.015 inches.
• Further, in some embodiments, these surface features can extend in a direction that is substantially lateral to a longitudinal axis (L) of a body, likecartridge body606 inFIG. 6. In another embodiment, at least a portion of the surface features can include a plurality of ridges and a plurality of grooves defined between the plurality of ridges. In yet another embodiment, these surface features can include a plurality of treads extending in a direction that is at least of upwardly from a body, inwardly toward a central groove, and distally toward a second end of the body. Additional details on anti-slip features that are in the form of ridges and grooves or in the form of treads can be found in U.S. Publication No. 2015/0034696, which is incorporated by reference herein in its entirety.
• In some embodiments, the plurality of surface features can be configured to pull tissue in opposite directions, and therefore provide a counter-resistance (e.g., lateral bias) to prevent the tissue from sliding during stapling. For example, the tissue-contacting layer can include a first plurality of surface features that can extend in a first direction and a second plurality of surface features that can extend in a second direction that is different than the first direction. As a result, the first and second plurality of surface features can create tension between the surface features that actively prevent motion of the tissue in at least one direction. In one embodiment, the first plurality of surface features can extend in a first direction and the second plurality of surface features can extend in an opposite second direction. In such instances, these surface features can be configured to pull tissue in opposite directions simultaneously.
• A counter resistance can also be created by surface bowing. For example, the tissue-contacting layer, or in the alternative, for example, the entire adjunct, can be designed to have a resilient convex shape, and the surface features can extend radially outward from the tissue-contacting layer. In use, as the anvil of the surgical stapler moves from an open to a closed position, as discussed above, the tissue-contacting layer can deform (e.g., compress to a substantially straight configuration), and the surface features, now extending substantially vertically outward from the tissue-contacting layer, engage tissue. As the anvil returns to its open position, the tissue-contacting layer returns to its convex shape creating a surface tension between the surface features that causes the engaged tissue to be pulled in opposite directions simultaneously.
• On the other hand, in certain embodiments, it can be desirable to have the tissue slide in a predefined plane during stapling. As such, in some embodiments, the tissue-contacting layer can include surface features that can be designed to promote slippage (e.g., a sliding movement) of the tissue relative to the adjunct in a first predetermined direction and to limit movement in a second direction that is different than the first direction. Alternatively, or additionally, the tissue-contacting layer can be coated with a material to increase lubricity (e.g., sodium stearate or lauric arginate ethyl ester).
• As discussed above, the adjunct is positioned atop a body, like cartridge body606 (FIG. 6). Prior to and during stapling, securement of the adjunct to the body can be enhanced. For example, the body-contacting layer (e.g., a cartridge-contacting layer) can include surface features that are configured to engage the body so as to substantially prevent sliding of the adjunct relative to the body. These surface features can have a variety of configurations. For example in embodiments where the body includes attachment features, the body-contacting layer can have surface features that are in the form of recesses that are configured to receive these attachment features. Other attachments features will be discussed in more detail below.
• As indicated above, the elongated body can be formed of a plurality of struts. These struts can form repeating geometric units interconnected to one another. As discussed in more detail below, the plurality of struts and/or the array of repeating units can be structurally configured to impart a varying compressibility to the adjunct, and thus the adjunct can have a variable stiffness profile. For example, the adjunct can have a first stiffness when compressed a first amount and a second stiffness when compressed a second amount. The second amount can be greater than the first amount or vice versa. Thus, the stiffness of the adjunct can vary as a function of compression. As discussed in more detail below, the greater the amount of compression, the greater the stiffness of the adjunct. Accordingly, a single adjunct can be tailored to provide a varied response that ensures a minimum amount of stress is applied to the tissue (e.g., 3 g/mm²) for at least a predetermined time (e.g., 3 days) under various stapling conditions (e.g., tissue thickness, height of formed staple, intra-tissue pressure). Further, this varied response by the adjunct can also desirably maintain the minimum amount of applied stress (e.g., 3 g/mm²) when the adjunct is stapled to tissue and exposed to fluctuations in intra-tissue pressure.
• These struts can be designed in various configurations. For example, these struts can produce lattice or truss-like structures as shown inFIGS. 8A-9C and 11A-15, spiral shaped structures as shown inFIG. 16, or columns as shown inFIGS. 17-19.
• The geometry of the struts themselves, as well as the geometry of the repeating units formed therefrom, can control movement of the adjunct in various planes. For example, the interconnectivity of the struts can create geometric units that can be configured to allow the adjunct to compress in a first predetermined direction and to limit movement in a second direction that differs from the first direction. As discussed in more detail below, in some embodiments, the second direction can be transverse to the first predetermined direction. Alternatively, or in addition to, the geometric units can be configured to limit rotational movement of the adjunct about an axis that is perpendicular to the first predetermined direction.
• In some embodiments, a strut can have a substantially uniform cross-section, whereas in other embodiments, the strut can have a varying cross-section. Additionally, the material of the strut can also play a role in defining movement of the adjunct in predetermined planes.
• FIGS. 8A-9C and 11A-19 illustrate various exemplary adjuncts that include a tissue-contacting surface, a cartridge-contacting surface that is opposite the tissue-contacting surface, and an elongate body formed of struts positioned therebetween. Each exemplary adjunct is illustrated in partial form (e.g., not in full-length), and therefore a person of ordinary skill in the art will appreciate that the adjunct can be longer in length, i.e., along its longitudinal axis L as identified in each embodiment. The length can vary based on a length of the staple cartridge. Further, each exemplary adjunct is configured to be positioned atop a cartridge body such that the longitudinal axis L of each adjunct is aligned with and extends along the longitudinal axis (L_C) of the cartridge body. Each of these adjuncts can be formed from one or more matrices that include at least one fused bioabsorbable polymer. These adjuncts are structured so as to compress when exposed to compressive forces (e.g., stress or load). As discussed in further detail below, these adjuncts are also designed to promote both tissue and cellular ingrowth.
• FIGS. 8A-8B illustrate an exemplary embodiment of an adjunct800 having a tissue-contactingsurface802, an opposite cartridge-contactingsurface804, and anelongate body806. While it is contemplated that the tissue-contactingsurface802, the cartridge-contactingsurface804, and theelongate body806 can each be formed from different materials, in this illustrated embodiment, they are formed of the same fused bioabsorbable polymer. That is, the adjunct800 is formed of a matrix of the same fused bioabsorbable polymer.
• As shown inFIG. 8A, theelongate body806 includes aplanar array808 of repeatingunits810 interconnected to one another at joints ornodes814. The repeatingunits810 are each formed of a plurality ofinterconnected struts816 that each have afirst portion818 and asecond portion820. Some of thestruts816 can also include athird portion821 that extends from their respective second portion and interconnect to one another to form the joints ornodes814. As discussed in more detail below, the adjunct800 can exhibit varying stiffness and movement based on the amount and direction of stress applied thereto during use. Thus, the adjunct has a variable stiffness profile such that when the adjunct is stapled to tissue, the adjunct can be configured to apply a stress at or above a minimum stress threshold for a predetermined time (e.g., a stress of 3 g/mm²for at 3 days).
• Further, as shown, theelongate body806 includes a firstplanar array808 of struts, and additionalplanar arrays808_Npositioned parallel to one another and to planar array808 (e.g., extending in the x-direction). In eacharray808,808_N, thestruts816 are substantially planar and extend co-planar with one another in a respective plane. Further, while eacharray808,808_Ncan have a variety of configurations, in this illustrated embodiment, eacharray808,808_Nis substantially symmetric about a mid-plane. That is, eacharray808,808_Nhas two substantially identical,rows824a,824bof repeatingunits810.
• While thestruts816 can have a variety of configurations, in this illustrated embodiment, eachstrut816 has a generally elongate planar configuration, with thefirst portion818 of eachstrut816 having a narrower width than a width section of thesecond portion820. As a result, thestruts816 are wider in the middle, preferably along a majority of the length, and narrower at the ends. Alternatively, thefirst portion818 can have a cross section that is equal to or greater that the cross section of thesecond portion820. Further, as shown inFIG. 8B, thesecond portion820 of eachstrut816 can have a substantially rectangular cross-sectional shape. It should be noted that other cross-sectional shapes of the struts, and portions thereof, are also contemplated herein. The cross-sectional shapes of the struts can be used to limit movement of the adjunct in certain directions.
• InFIG. 8A, thestruts816 are interconnected to one another at an end of theirfirst portion818 to form joints ornodes822. In the illustrated embodiment, thestruts816 and the joints ornodes822 can be formed of the same material. Thus, to enhance the compression of the adjunct800 under stress, the cross-section of thefirst portion818, also referred to as a neck down region, can flex as described in more detail below. Further, thethird portion821 of therespective struts816 is similarly structured like thefirst portion818 of thestruts816, and therefore thisthird portion821, also referred to as a neck down region, can also flex as in more detail below.
• The material of the joints ornodes822 relative to the struts816 (e.g., more or less flexible) can control, in part, the amount and/or direction at which the adjunct800 moves under stress during use. Likewise, the material of the joints ornodes814 can control, in part, the amount and/or direction at which the adjunct800 moves under stress during use. The joints ornodes814,822 can be any suitable shape. For example, in certain embodiments, the joints ornodes814,822 can be in the form of a ball-shaped feature. In other embodiments the joints ornodes814,822 can take the form of other geometric shapes.
• Thestruts816 can be interconnected to each other at various angles. For example, in this illustrated embodiment, thestruts816 intersect at about 90 degree angles relative toadjacent struts816. In other embodiments, thestruts816 can intersect at angles in a range of about 40 degrees to 130 degrees. In another embodiment, thestruts816 can intersect at angles in a range of about 10 degrees to 90 degrees. The angles at which thestruts816 connect to each other can control, at least in part, the manner and the amount in which the adjunct800 responds under stress. That is, the movement and stiffness of the adjunct800 can be, at least in part, a function of these angles.
• As mentioned above, the first portion818 (and thethird portion821 where present) of eachstrut816 can act as a flexible region for the adjunct (e.g., a deflection point). Thefirst portion818 of each strut provides each repeating unit812 with one or more bend zones, as illustrated inFIGS. 9A-9C. That is, these neck down regions allow thestruts816 to bend about or adjacent to the joints ornodes822 when the adjunct800 is under stress, and therefore the repeatingunits810 can partially or fully collapse upon themselves. Similarly, the neck down regions that form thethird portion821 allow the repeating units to bend about or adjacent to the joints ornodes814 when the adjunct is under stress. The compressibility of the adjunct800 can therefore vary based on different amounts and directions of applied stress. This variation in compressibility can be desirable, for example, when the adjunct is stapled to tissue and exposed to fluctuations in intra-tissue pressure.
• FIGS. 9A-9C illustrate the compression behavior of one repeatingunit810 ofadjunct800 as described herein under different stresses. In particular, the repeatingunit810 is shown in an pre-compressed (undeformed) state inFIG. 9A, a first compressed state under a first stress (S₁) inFIG. 9B, and a second compressed state (C) under a second stress (S₂) inFIG. 9C. As such, the repeatingunit810, and thus adjunct800, has a variable stiffness profile under different stresses. A person of ordinary skill in the art will appreciate that the adjunct can have a variety of deployed heights throughout its use, and that the deployed heights are a function of, at least in part, the particular stresses that are applied to the adjunct throughout its use.
• As shown inFIGS. 9A-9B, when the repeatingunit810, and thus adjunct800 inFIG. 8A, is under a first stress S₁, the first portion818 (e.g., the neck down region) of eachstrut816 can bend about the joint ornode822. This allows the repeatingunit810 to compress from a pre-compressed state (FIG. 9A) to a first compressed state (FIG. 9B), and thus adjunct800 from a pre-compressed height to a first deployed height. Further, depending on the amount of stress applied to the adjunct, thesecond portion820 ofadjacent struts816 can come into contact with each other. This is illustrated inFIG. 9B. In such instances, thefirst portion818 of eachstrut816 has therefore reached a maximum deflection point creating a greater stiffness resistance within the repeatingunit810. This is because the stiffness of the repeatingunit810, and thus the adjunct800, increases as the adjunct800 compresses.FIG. 10 is an exemplary graph representation of the relationship between compression and stiffness of an adjunct. Thus, any further compression of the repeating810, and thus the adjunct800 would require an additional applied stress.
• In circumstances where a greater stress (e.g., second stress, S₂) is applied to the repeatingunit810, and thus adjunct800 inFIG. 8A, the increase in stiffness resistance can be overcome. To achieve this, thestruts816 can be configured such that when additional stress is applied, thestruts816 can further bend about the joint ornode822. As shown inFIG. 9C, this further bending can cause thestruts816 to further expand outward in a direction lateral (L) to the direction of applied stress, whereby causing thesecond portions820 ofadjacent struts816 to come into further contact with each other. As a result, this allows the repeatingunit810 to compress to a second compressed state (FIG. 9C), and thus adjunct800 to a second deployed height.
• In some embodiments, the adjunct can include additional components that can prevent movement of tissue that is stapled to the adjunct. For example,FIGS. 11A-11B illustrate anexemplary adjunct1100 that includes a plurality of surface features1128 defined within the tissue-contactinglayer1102. As described in more detail below, the surface features1128 can prevent slidable movement of the adjunct relative to tissue stapled to the adjunct. In one embodiment, at least a portion of the surface features1128 can prevent lateral sliding of the adjunct1100 relative to the tissue. Alternatively, or in addition to, at least a portion of the surface features1128 can prevent longitudinal sliding of the adjunct1100 relative to the tissue.
• The illustratedexemplary adjunct1100 includes a tissue-contactinglayer1102 and an opposite cartridge-contactinglayer1104. The adjunct1100 also includes anelongate body1106 having a plurality ofstruts1116 extending between the tissue-contactinglayer1102 and the cartridge-contactinglayer1104. As shown, the tissue-contactinglayer1102 includes a plurality of surface features1128a,1128bdefined therein. These surface features1128 have a grid-like pattern with afirst series1128aextending longitudinally (e.g., parallel to the longitudinal axis of the adjunct) and asecond series1128bextending laterally (e.g., traverse to the longitudinal axis of the adjunct). Eachsurface feature1128a,1128bcan have a triangular profile, or at least two surfaces that are angled relative to one another and that come together to form an edge so as to penetrate into and engage tissue. These edges collectively can define the outer-most surface of the tissue-contactinglayer1102. These surface features1128a,1128bcan engage tissue when the tissue is compressed into the tissue-contactinglayer1102 as a result of the adjunct being stapled to tissue. The orientation of the edges of thefirst series1128acan prevent lateral sliding of the adjunct relative to the tissue and the orientation of the edges of thesecond series1128bcan prevent longitudinal sliding of the adjunct1100 relative to the tissue. Further, the tissue-contactinglayer1102 includes a plurality ofopenings1144 that are formed between these surface features1128. In this way, the plurality ofopenings1144 can receive tissue therein when the adjunct is stapled to tissue to allow the surface features1128 to engage the tissue.
• While the plurality ofstruts1116 can be interconnected to form a variety of configurations, in this illustrated embodiment, the plurality ofstruts1116 form repeating X patterns. In particular, the plurality ofstruts1116 form repeating cubic units. Each cubic unit includes atop surface1130, and an opposingbottom surface1132. In this illustrated embodiment, the top andbottom surfaces1130,1132 are substantially identical. The cubit unit also includes fourside surfaces1134 extending between and connecting the top andbottom surfaces1130,1132. In this illustrated embodiment the side surfaces1134 are substantially identical. For clarity, not all surfaces of each illustrated cubit unit are identified inFIGS. 11A-11B. The side surfaces1134 can have a variety of shapes, for example, as shown eachside surface1134 has an X shape that extends from the top to the bottom surfaces1130,1132. As such, the first end of eachstrut1116,1116aterminates at the tissue-contactinglayer1102 and the second end of eachstrut1116,1116aterminates at the cartridge-contactinglayer1104. Each X can be formed by two elongated, generally planar struts that intersect at a mid-portion. Further, each repeating cubic unit can also include an internal strut that extends between twoopposite side surfaces1134 of the cubic unit to form aninner connectivity feature1138. As shown, theinner connectivity feature1138 can extend from the top1134aof oneside surface1134 to the bottom1134bof an opposingside surface1134. As further shown, the inner connectivity features1138 can extend in alternating directions between adjacent cubic units. For example, as shown inFIG. 11B, a firstinner connectivity feature1138 can have anupper end1138athat extends from the top1134aof oneside surface1134 to alower end1138bat the bottom1134bof theopposite side surface1134, and the adjacent cubic unit can have a secondinner connectivity feature1138 with alower end1138cthat extends from thesame bottom1134bof theside surface1134 to anupper end1138dat a top1134cof anopposite side surface1134. The inner connectivity features1138 can provide the adjunct1100 with a geometry that can promote predetermined directional movement of the adjunct1100 under applied stress. For example, in one embodiment, the inner connectivity features1138 can substantially prevent shearing of the adjunct1100 under applied stress.
• While each strut, as well as the interconnectivity features1138, can have a variety of configurations, in this illustrated embodiment, thestruts1116,1116aand the interconnectivity features1138 are each in the form of a beam or column having a width (W) that is greater than a depth (D) such that each strut/interconnectivity feature is limited to bending in a predetermined direction, i.e., in and out of the plane extending along the width (W). Further, thestruts1116,1116aand the interconnectivity features1138 can each include at least oneopening1140 extending therethrough to facilitate bending in a predetermined direction. For clarity purposes, not allopenings1140 extending through eachstrut1116 and the interconnectivity features1138 are identified inFIGS. 11A-11B. Theseopenings1140 can a variety of shapes, for example, as shown, theseopenings1140 are diamond shaped. It is also contemplated that the shape of theopenings1140 can vary among struts. Theopenings1140 can also be aligned throughout the adjunct. For example, openings extending through opposite sidewalls spaced longitudinally along the length of the adjunct in adjacent cubic units can be aligned longitudinally, and similarly openings extending through opposite sidewalls spaced laterally along the width of the adjunct in adjacent cubic units can be aligned laterally.
• Alternatively, or additionally, the adjunct can include linking members that connect at least a portion of the joints or nodes to each other to thereby increase the stiffness of the adjunct. That is, the linking members can be incorporated into the adjunct so as to prevent movement (e.g., splaying) of the adjunct in the planes in which the linking members extend.
• For example,FIGS. 12A-12B illustrate an exemplary embodiment of an adjunct1200 having linkingmembers1246. In particular, the adjunct1200 includes anelongate body1206 formed of a plurality ofstruts1216 that are interconnected at joints ornodes1222. Theelongate body1206 has a tissue-contactingsurface1202 and an opposite cartridge-contactingsurface1204. As shown, at least a portion of these joints ornodes1222 are interconnected to each other by linkingmembers1246. In this illustrated embodiment, the linking members1230 extend in a first direction (e.g., the y-direction as shown inFIG. 12) and thestruts1216 extend in a second direction that is different than the first direction (e.g., a transverse direction, such as about 45 degrees relative to the y-direction as shown inFIG. 12). Thus, the position of the linkingmembers1246 relative to thestruts1216 can provide the adjunct1200 with a geometry that can be configured to prevent movement of the adjunct1200 in at least in one direction (e.g., a direction parallel to the direction in which the linkingmembers1246 extend).
• In some embodiments, the joints or nodes can be formed of material that differs from the material of the struts. For example, the material of the joints or nodes can be more flexible than the material of the struts, thereby increasing the compressibility of the adjunct. Further, the more flexible joints or nodes can also allow the adjunct to compress without substantially shearing. This is because the more flexible joints or nodes provide preferential bending zones for the adjunct, thereby decreasing the stiffness of the adjunct. In one embodiment, the joints or nodes can be formed of a polycaprolactone copolymer and the struts can be formed of polyglactin or polydioxanone.
• FIGS. 13A-13B illustrate another exemplary embodiment of an adjunct1300 that includes repeatingunits1310 interconnected to one another at joints ornodes1314. The repeatingunits1310 are each formed of a plurality ofstruts1316, e.g., four struts, that interconnect at joints ornodes1322. Aside from the differences described in detail below, the adjunct1300 can be similar to adjunct800 (FIG. 8A) and is therefore not described in detail herein. In this illustrated embodiment, the joints ornodes1314,1322 are formed of a different material than the material of thestruts1316. The material of the joints ornodes1314,1322 can be more flexible than the material of thestruts1316. As shown, each joint ornode1314,1322 can be in the form of arod1348 that extends across allarrays1308,1308_Nin a direction that is generally perpendicular to the plane in which the struts extend (e.g., the rods can extend in the x-direction as shown inFIGS. 13A-13B). That is, when the adjunct1300 is attached to a cartridge body, therods1348 can extend laterally relative to the longitudinal axis of a cartridge body, likecartridge body606 inFIG. 6.
• In some embodiments, as shown inFIGS. 13A-13B, the ends of thefirst portions1318 of thestruts1316 can also be directly connected to each other within the joints ornodes1322. Alternatively, or additionally, the ends of thethird portions1321 of thestruts816 can also be directly connected to each other within the joints ornodes1314. This direct connection can help prevent thestruts1316 from pulling out of the joints ornodes1322 as thestruts1316 bend when the adjunct1300 is under stress. As a result of this direct connection, the bending of one strut can also influence the bending of another. Further, as compared to joints ornodes822 inFIG. 8A, these joints ornodes1322 can be more flexible, thus more compliant, and the adjunct1300 can therefore compress more easily compared toadjunct800. As such, under the same given stress, the adjunct1300 will achieve a greater displacement (i.e., compress to a lower deployed height) as compared toadjunct800 inFIG. 8A.
• Alternatively, the struts can be unconnected relative to each other within the joints or nodes, for example, as shown inFIG. 14. For simplicity purposes only,FIG. 14 illustrates a single repeatingunit1400. In this illustrated embodiment, thestruts1416 do not directly connect to one other within the joint ornode1422. As a result, the bending of one strut can occur independent of the bending of another strut. To prevent thestruts1416 from pulling out of the joint ornode1422 when thestruts1416 bend thereabout, eachstrut1416 can have anend shape1450 configured to maintain its connection to the joint ornode1422. Further, as compared to joints ornodes1322 inFIGS. 13A-13B, this joint ornode1422 can be more flexible, and thus more compliant, and therefore an adjunct formed of various repeatingunits1400 can compress more easily under a given stress. That is, under the same given stress, an adjunct with this illustrated strut and joint or node configuration can achieve a greater displacement (i.e., compress to a lower height) as compared toadjunct800 inFIGS. 13-13A.
• In some embodiments, the adjunct can also include at least one stop element that is configured to limit the amount of compression of the adjunct.FIG. 15 illustrates an exemplary embodiment of an adjunct1500 having at least onestop element1552. Aside from the differences described in detail below, the adjunct1500 can be similar to adjunct1300 (FIGS. 13A-13B) and is therefore not described in detail herein.
• InFIG. 15, eachstrut1516 can have astop element1552 extending from or positioned adjacent to a surface of itssecond portion1520. As the adjunct1500 is compressed, thestruts1516 can bend about the joint ornodes1514,1522 until thestop elements1552 come into contact with each other. Once thesestop elements1552 abut one another, any further bending of thestruts1516 will be inhibited. That is, thesestop elements1552 act as deflection stops that allow the adjunct1500 to compress under a given stress to a first deployed height at a first stiffness. Upon reaching the first compressed height, thestop elements1552 bottom out and inhibit further deflection of thestruts1516, and thus further compression of the adjunct1500. Once thestop elements1552 bottom out, a greater amount of stress needs to be applied to effect further bending of thestruts1516 about the joints ornodes1514,1522 and thus further compression of the adjunct1500.
• It should be noted that whilevarious stop elements1552 are shown inFIG. 15, it is contemplated herein that fewer or additional stop elements can be included throughout the adjunct1500. Further, the shape, size, and location of thestop elements1552 are not limited by this illustrated embodiment, and therefore can vary to control the desired amount of compression.
• As mentioned above, the elongated body can include a plurality of struts that can have a variety of shapes. For example,FIG. 16 illustrates anexemplary adjunct1600 having anelongate body1606 that includes a plurality ofstruts1616 that are substantially spiral-shaped. As such, each repeating geometric unit is in the form of a spiral or coil. In this embodiment, theelongate body1606 is positioned between a tissue-contactinglayer1602 and a cartridge-contactinglayer1604. As shown, eachlayer1602,1604 are generally planar solid layers withopenings1626. At least a portion of theseopenings1626 are aligned with theopenings1615 defined by eachstrut1116. The thickness of each layer can vary. Thestruts1616 are configured to have predetermined compressed heights to limit an amount of compression of the adjunct. Further, given their shape, thesestruts1616 can be configured to function as a spring. Thus, similar to a spring constant, a specific stiffness can be imparted to eachstrut1616 based on its shape. Thus, the compressibility of the adjunct1600 can also be dependent on the specific stiffness of eachstrut1616, which is dependent on both the material and shape of thestrut1616.
• As shown inFIGS. 8A, 11A-13B, and 15-16, each adjunct800,1100,1200,1300,1500,1600 can includeopenings826,1140,1144,1226,1326,1526,1626. These openings can be configured to promote cell ingrowth within each adjunct. The openings can define a void content of the adjunct. In some embodiments, the void content can be from about 15% to 95%, whereas in other embodiments, the void content can be from about 75% to 90%. As used herein, “openings” is used synonymously with “voids”. Further, the adjunct can have a surface area to volume ratio of about 1:100 to 1:5. In some embodiment, the adjunct can have a surface area to volume ratio of about 1:10.
• The openings can also be located within various components of the adjuncts. Each opening can have a dimension extending at least partially through the component. In certain embodiments, as shown inFIGS. 8A, 11A-13B, and 15-16, theopenings826,1140,1444,1226,1326,1526,1615,1626 can be present within the tissue-contacting surface or layer, the cartridge contacting surface or layer, and/or the elongated body. In these illustrated embodiments, these openings extend completely through its respective component. Within the elongate body, these openings can be defined by the interconnected struts. Further, these openings can also be interconnected throughout the adjunct to thereby form a substantially continuous network of openings or channels. Further, as shown inFIGS. 11A-11B, openings1126 can also be present within inner connectivity features1138.
• The openings can have varying sizes and/or shapes. For example, larger openings can allow tissue (and cells) to penetrate into the adjunct while smaller openings can trap cells within the adjunct to promote cell ingrowth. In this way, the variable opening sizes throughout the adjuncts can promote extracellular remodeling. That is, the variable opening sizes can facilitate revascularization as well as mobility of cells within the adjunct when the adjunct is implanted, thereby encouraging both tissue and cellular ingrowth. Further, the variable opening sizes can also facilitate extraction of byproducts and cellular waste from the implanted adjunct, and thus the implantation site. In some embodiments, the openings are substantially circular-shaped.
• In embodiments where openings are located within the tissue-contacting surface or layer and the elongate body, such as inFIGS. 8A, 11A-13B, and 15-16, the openings can each have a diameter that is about 70% to 170% of a diameter of a staple leg of a staple, likestaple406 inFIGS. 4-5. The openings within the tissue-contacting surface and within the elongate body can have a variety of sizes. For example, in some embodiments, the openings in the tissue-contacting surface can each have a diameter in the range of about 100 μm to 1000 μm. In one embodiment, the openings in the tissue-contacting surface can each have a diameter that is at least about 14 μm. The openings in the elongate body can each have a diameter in the range of about 200 μm to 610 μm or of about 400 μm to 1000 μm. As used herein, “diameter” of an opening is the largest distance between any pair of vertices of the opening.
• Further, in some embodiments, the openings within the tissue-contacting surface or layer can be configured to allow one or more portions of tissue to penetrate or compress into the tissue-contacting surface or layer (e.g.,openings1144,1226,1626). In this way, as discussed above, when the adjunct is stapled to tissue and the tissue is compressed into the opening, slidable movement of adjunct relative to the tissue can be substantially prevented.
• In other embodiments, the adjunct can be configured to enhance staple leg advancement through the adjunct. For example, the adjunct can have openings that are aligned with the advancement direction of the staple legs into and partially through the adjunct. The openings can extend partially or completely through the adjunct. Thus, as the staple legs advance through the adjunct, the openings can act as a guide to minimize damage to the staple, as well as the adjunct, as the staple passes therethrough.
• In some embodiments, as shown inFIGS. 17-19, the adjunct can include a plurality of struts that are in the form of columns. For example, inFIG. 17, the columns can be substantially vertical and of varying heights. Further, in other embodiments, as shown inFIG. 19, a first set of columns can be substantially vertical and a second set of columns can be curved. The struts can be formed of the same or different material. In some embodiments, the adjunct can include a first plurality of struts that are formed of a first material and a second plurality of struts that are formed of a second material.
• InFIG. 17, the adjunct1700 includes a plurality ofstruts1716 that are in the form of substantially vertical columns. In particular, thesestruts1716 extend from a cartridge-contactinglayer1704 toward, and in some instances to, the opposing tissue-contactinglayer1702. The plurality ofstruts1716 includes a first plurality ofvertical struts1716ahaving a first height (Y), a second plurality ofstruts1716bhaving a second height (Y₁) that is less than the first height (Y), and a third plurality ofstruts1716chaving a third height (Y₃) that is less than the second height (Y₂). For simplicity, only a portion of the plurality ofstruts1716 are shown inFIG. 17. While not shown, a person of ordinary skill will appreciate that the tissue- and/orcartridge contacting layers1702,1704 can include openings as discussed herein.
• The varying heights of these plurality ofstruts1716 can provide the adjunct with varying compressibility.FIGS. 18A-18C illustrate the compression behavior of adjunct1700 under different stresses. In particular, the adjunct1700 is shown at a pre-compressed height inFIG. 18A, a first compressed height (H₁) under a first stress (S₁) inFIG. 18B, and a second compressed height (H₂) under a second stress (S₂) inFIG. 18C. As shown, the first compressed height (H₁) is greater than the second compressed height (H₂), and therefore the first stress (S₁) is less than the second stress (S₂). A person of ordinary skill in the art will appreciate that the adjunct can have a variety of compressed heights throughout its use, and that the compressed heights are a function of, at least in part, the particular stresses that are applied to the adjunct throughout its use.
• As shown inFIGS. 18A-18C, as the compression of the adjunct1700 increases, the amount of stress needed to achieve such compresses increases. This is because additional struts are engaged as the adjunct1700 compresses, thereby increasing the stiffness resistance of the adjunct1700. For example, as shown inFIG. 18B, at a first stress S₁applied to the adjunct1700, the first and second plurality ofstruts1716a,1716bare engaged. In comparison, when the adjunct1700 is under a second stress S₂, the first, second, and third plurality ofstruts1716a,1716b,1716care engaged, thereby creating a greater stiffness resistance.
• FIG. 19 illustrates another exemplary embodiment of an adjunct1900 having a plurality ofstruts1916 that are in the form of substantiallyvertical columns1916aorcurved columns1916b.The substantiallyvertical columns1916acan be configured to support the initial stress applied to the adjunct1900, and then deflect or buckle (e.g., at deflection point D inFIG. 20) as the adjunct compresses. Thecurved columns1916bcan configured to provide approximately constant stiffness (i.e., essentially the offset of the whole curve shown inFIG. 20 from the zero axis). This mechanical behavior of thestruts1916, and thus the adjunct1900, is graphically represented inFIG. 20.
• In other embodiments, the adjunct can include additional features. The following figures illustrate features that can be included on any of the adjuncts disclosed herein, and thus the specific configuration of the adjunct, i.e., the configuration of the repeating units, is not shown.FIG. 21A illustrates one embodiment of an adjunct2100 having achannel2108 formed therein that is configured to receive a cutting element, such as a knife.
• As shown inFIG. 21A, the adjunct2100 includes afirst portion2104 and asecond portion2106, each having outer and inner edges. Theinner edges2104a,2106adefine achannel2108 that extends between the first and second portions and along the longitudinal axis (L) of the adjunct2100. Thechannel2108 is configured to receive a cutting member, such as a knife. As shown inFIG. 121B, the channel21 does not extend completely through the height of the adjunct2100. In particular, thechannel2108 does not extend through the cartridge-contactingsurface2110. In this way, the adjunct2100 is configured to have sufficient structural integrity to thereby be effectively manipulated and attached to a cartridge body, likecartridge body2214 inFIG. 21B. In use, when the cutting member is initially fired and travels along the adjunct, the cutting member cuts through the channel, thereby separating the first and second portions, and thus separating the adjunct2100 into two separate pieces.
• Further, as shown inFIG. 21A, the adjunct2100 includesflanges2112 that are configured to mate with acartridge body2214 inFIG. 21B, as further described below. WhileFIG. 21A illustrates the adjunct2100 havingflanges2112 at one side of the adjunct2100,additional flanges2112 can be present on the opposite side of the adjunct2100. A person skilled in the art will appreciate that the number and placement offlanges2112 are not limited to what is shown inFIG. 21A. While theflanges2112 can be made of a variety of materials, in some implementations, as shown inFIG. 21A, theflanges2112 can be an extension of the cartridge-contactingsurface2110. A person skilled in the art will appreciate that the flanges can be formed in-line with the adjunct (e.g., as part of the 3D printing process), or in the alternative formed off-line and then secondarily applied to the adjunct.
• FIG. 21B illustrates an embodiment of astaple cartridge assembly2200. Aside from the differences described in detail below, thestaple cartridge assembly2200 can be similar to staple cartridge assembly600 (FIG. 6) and is therefore not described in detail herein. Further, for purposes of simplicity, certain components of thestaple cartridge assembly2200 are not illustrated inFIG. 21B.
• Thestaple cartridge assembly2200 includes the adjunct2100 inFIG. 21A attached to acartridge body2214. The adjunct2100 can be attached to thecartridge body2214 using any suitable methods, as described in more detail below. In this embodiment, thecartridge body2214 includes recessedchannels2216 that are configured to receive theflanges2112 on the adjunct such that theflanges2112 can engage the side(s) of thecartridge body2214. In this way, the adjunct2100 can be more securely attached to the cartridge body, thereby preventing undesired movement of the adjunct2100 during use.
• In another embodiment, as shown inFIG. 22, the adjunct3000 can have achannel3008 that has one ormore openings3010 extending therethrough (e.g., perforated), thereby creating at least onebridging member3012. As such, the first andsecond portions3014,3016 of the adjunct3000 are selectively connected by the at least onebridging member3012. In use, when the cutting member is initially fired and travels along the adjunct3000, the cutting member cuts through the at least onebridging member3012, thereby separating the first andsecond portions3014,3016, and thus separating the adjunct3000 into two separate pieces.
• In some embodiments, the cartridge body, likecartridge body2214 inFIG. 21B, and the adjunct, like adjunct3000 inFIG. 22, can include complementary reinforcement features that can be configured to prevent tearing of the adjunct outside of the channel when the cutting element moves through the adjunct3000. For example, the reinforcement features of the cartridge body can be cylindrical recessed openings positioned proximate to the slot within the cartridge body and the reinforcement features of the adjunct can be cylindrical protrusions positioned within the first and second portions of the adjunct proximate to the at least one bridging member. In this way, when the adjunct is placed atop the cartridge body, these cylindrical protrusions of the adjunct will extend into these recessed openings of the cartridge body. It is also contemplated that these protrusions and recessed openings can take the form of other various shapes.
• The scaffolds can be applied to a cartridge body to form a staple cartridge assembly using any suitable method. For example, in some embodiments, the method can include attaching a compressible, bioabsorbable adjunct to a cartridge body of a surgical stapler. In one embodiment, as discussed above, the attachment of the adjunct to the cartridge body can include placing a cartridge-contacting surface of the adjunct against a surface of the cartridge body so as to insert flanges of the adjunct into recessed channels of the cartridge body. In another embodiment, the method can also include coating a surface of the cartridge body with an adhesive prior to attaching the adjunct thereto.
• The devices disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. In either case, however, the device can be reconditioned for reuse after at least one use. Reconditioning can include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular pieces and subsequent reassembly. In particular, the device can be disassembled, and any number of the particular pieces or parts of the device can be selectively replaced or removed in any combination. Upon cleaning and/or replacement of particular parts, the device can be reassembled for subsequent use either at a reconditioning facility, or by a surgical team immediately prior to a surgical procedure. Those skilled in the art will appreciate that reconditioning of a device can utilize a variety of techniques for disassembly, cleaning/replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.
• One skilled in the art will appreciate further features and advantages of the invention based on the above-described embodiments. Accordingly, the invention is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. All publications and references cited herein are expressly incorporated herein by reference in their entirety. Any patent, publication, or information, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated material does not conflict with existing definitions, statements, or other disclosure material set forth in this document. As such the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference.

Claims (18)

What is claimed is:

1. A stapling assembly for use with a surgical stapler, comprising:

a body having a plurality of staples disposed therein, the plurality of staples being configured to be deployed into tissue; and

a three-dimensional compressible adjunct formed from a matrix comprising at least one fused bioabsorbable polymer and configured to be releasably retained on the body such that the adjunct can be attached to the tissue by the plurality of staples in the body, wherein the adjunct has a variable stiffness profile such that when the adjunct is in a tissue deployed state, the adjunct is configured to apply a stress at or above a minimum stress threshold to the tissue for at least about 3 days.

2. The stapling assembly ofclaim 1, wherein the plurality of staples have a height of about 0.130 inches or less when in a formed configuration.

3. The stapling assembly ofclaim 1, wherein the minimum stress threshold is at least about 3 g/mm².

4. The stapling assembly ofclaim 1, wherein the adjunct has a stiffness that increases as the adjunct compresses.

5. The stapling assembly ofclaim 1, wherein the adjunct has compressible internal struts that are substantially spiral-shaped and have a predetermined compressed height to limit an amount of compression of the adjunct.

6. The stapling assembly ofclaim 1, wherein the adjunct includes at least one stop element configured to limit an amount of compression of the adjunct.

7. The stapling assembly ofclaim 1, wherein the adjunct has a plurality of interconnected struts each having two bend zones, the first bend zone being configured to bend when the adjunct is compressed under a first stress and the second bend zone being configured to bend when the adjunct is compressed under a second stress that is greater than the first stress.

8. The stapling assembly ofclaim 1, wherein the adjunct has a plurality of internal substantially vertical columns.

9. The stapling assembly ofclaim 8, wherein the plurality of columns includes a first set of columns having a first length and a second set of columns having a second length that is less than the first length.

10. The stapling assembly ofclaim 1, wherein the at least one fused bioabsorbable polymer is selected from the group consisting of thermoplastic absorbable polyurethane, ultraviolet curable absorbable polyurethane, poly(lactic acid), polycaprolactone, polyglycolide, polydioxanone, poly(lactic-co-glycolic acid), polyglycolic acid, trimethylene carbonate, glycolide, dioxanone, polyester, copolymers thereof, and combinations thereof.

11. A stapling assembly for use with a surgical stapler, comprising:

a body having a plurality of staples disposed therein, the plurality of staples being configured to be deployed into tissue; and

a three-dimensional compressible adjunct formed from a matrix comprising at least one fused bioabsorbable polymer and configured to be releasably retained on the body such that the adjunct can be attached to tissue by the plurality of staples in the body, wherein the adjunct has a first stiffness when compressed a first amount and a second stiffness when compressed a second amount greater than the first amount.

12. The stapling assembly ofclaim 11, wherein the adjunct has compressible internal struts that are substantially spiral-shaped and have a predetermined compressed height to limit an amount of compression of the adjunct.

13. The stapling assembly ofclaim 11, wherein the adjunct includes at least one stop element configured to limit an amount of compression of the adjunct.

14. The stapling assembly ofclaim 11, wherein the adjunct has a plurality of interconnected struts each having two bend zones, the first bend zone being configured to bend when the adjunct is compressed the first amount and the second bend zone being configured to bend when the adjunct is compressed the second amount.

15. The stapling assembly ofclaim 11, wherein the adjunct has a plurality of internal substantially vertical columns.

16. The stapling assembly ofclaim 15, wherein the plurality of columns includes a first set of columns having a first length and a second set of columns having a second length that is less than the first length.

17. The stapling assembly ofclaim 11, wherein the at least one fused bioabsorbable polymer is selected from the group consisting of thermoplastic absorbable polyurethane, ultraviolet curable absorbable polyurethane, poly(lactic acid), polycaprolactone, polyglycolide, polydioxanone, poly(lactic-co-glycolic acid), polyglycolic acid, trimethylene carbonate, glycolide, dioxanone, polyester, copolymers thereof, and combinations thereof.

18. The stapling assembly ofclaim 11, wherein the adjunct is configured to apply a stress of at least about 3 g/mm²to the tissue stapled thereto for at least 3 days when the adjunct is in a tissue deployed state.

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